Design And Implementation Of Presence Server Based On SIMPLE

Presence is a kind of very important value-added way in the multimedia communication.At present,existing Presence systems are all integrated with IM,but Presence business has not limited to instant communication system,various kinds of communication mode will use Presence business,it is necessary to let Presence separate,as a alone application server.Under such a background,it is very significant to realize the Presence Server which supports the SIMPLE standard.SIMPLE is a Presence technology standard based on the SIP expansion,its support for many new feature of Presence is relatively mature,this text will design and implement the Presence Server based on this standard.This paper studies and analyzes a large number of standard document and draft that was issued in recent years by SIMPLE standard,designing RLS subscription、subscription authorization、state-based access control 、 watcher information and other new Presence feature.In the SIM standard system, the Addressbook and Presence operates independently,when the staff or privilege of the addressbook changes,it needs the client change its user list and update the presence subscription manually,this not only increases the network consumption and the load of the Presence Server,but also influences the user experience.To solve this problem,this text proposes a method to make the Addressbook and Presence integrate.This paper develops the Presence Server using the C and Python language in the Ubuntu operating system,this server satisfies the basic requirement of the Presence system,and it can communicate with various SIP client that supports the SIMPLE standard,it has good expansibility.At the same time,on the basis of the server,this text realizes the integration of the Addressbook and Presence perfectly,it makes the staff get his user list within his permission scope and the Presence state once.Thus,it reduces the network consumption and the load of the Presence Server and enhances the user experience.